This invention relates to an improved film-forming composition for providing a barrier film on the skin to protect the skin from irritation by body fluids and adhesively secured appliances as encountered by ostomates.
As is very often the case with the use of an ostomy appliance, a significant problem exists with respect to avoiding skin irritation. The important concept in skin breakdown is that the natural barrier properties of the skin have been breached and the body is now vulnerable.
With an ostomy, the continuous application and removal of aggressive adhesively secured appliances creates a maceration of the outer protective layer of the skin. When this layer is stripped away, the inner, i.e., living, layer containing the glands, blood vessels, nerves and muscle fiber is particularly vulnerable to the corrosive effects of feces and urine, and severe skin damage can occur.
In the case of the ileostomate, continuous application and removal of adhesively secured appliances as well as the acidity, the enzymatic activity and bacteria of the stomal discharge can create havoc around the stoma.
More common to all ostomates are the monilial infections that occur in the moist, dark environments found under appliances.
A frequent recommendation in this condition is the use of a skin barrier at the interface between the skin and appliance adhesive. However, many of the prior barriers suggested exacerbate the very problems they are intended to alleviate. For example, most preformed wafer barrier devices are occlusive since moisture vapor coming off the skin cannot pass through them. Moisture is thus trapped to a greater or lesser extent, depending upon the type of barrier used. Also, light cannot pass through such barriers, creating a dark as well as a moist environment that is ideal for further yeast growth.
The ostomate is not the only one whose skin comes under attack from adverse conditions. Permanently or temporarily disabled persons find themselves confronted by similar situations. Any time one is subjected to immobility, compounded by incontinence of bladder or bowel, skin-threatening conditions can occur. In all cases one common denominator exists. The natural barrier protection offered by the skin has been compromised.
Attempts have been made in the past to provide a skin coating material in the form of a liquid which may be applied to the skin by a sponge or other means. Because the liquid is extremely fluid, it was difficult to maintain the liquid in place until it had dried, and often the user was required to lie on their back while applying the liquid and permitting the same to dry to form a protective coating. This provided a far from satisfactory means for attempting to establish a skin coating.
It is recognized as described in U.S. Pat. No. 3,269,903 that a significant problem with liquid plastic dressings is a lack of adequate diffusion of vapor after the solvent evaporates leaving a film. The patent is directed to attempting to solve this major problem that is attributed to the inclusion of plasticizers in the liquid dressing compositions. The patent is thus principally directed to the provision of plasticizer-free liquid plastic dressings such as consisting of solutions of polymeric-2-methoxyethylmethacrylate or polymeric-2-ethoxyethyl-methacrylate for forming a vapor permeable skin coating. In comparing the vapor permeability of the coatings of the invention with coatings formed of other polymers, the permeability of films of polybutyl methacrylate per se and polyisobutyl methacrylate per se were investigated and found to be meager and thus presumably not suitable for the intended utility. However, problems that may be encountered with the polymeric-2-ethoxyethyl methacrylate film of this patent are briefly discussed in U.S. Pat. No. 3,987,000, see column 3.
Other attempts as exemplified by U.S. Pat. No. 3,876,771, have provided a skin coating or skin protective material in the form of a gel. The gel is sufficiently stiff as to be able to support itself in position without running, even when applied to the skin surface surrounding the stoma while the person is standing. While the gel is capable, under favorable conditions, of drying to a thin protective coating against which the adhesive or other sealing means of the ostomy appliance may be pressed, the film formed on the skin is generally relatively soluble in water, especially soapy water. Thus, stomal fluid discharges and particularly ileal conduit discharges, which are primarily water, adversely effect the integrity of the barrier formed.
With further reference to U.S. Pat. No. 3,987,000, it will be seen that it is known, particularly in connection with compositions that can be sprayed from aerosol containers, that a mixed polymeride derived by mixed polymerization of isobutene with lower acrylic or methacrylic acid esters and maleic acid monoesters, and wherein the patent is primarily directed to providing a non-blocking film by the addition of the maleic acid monoesters to the monomer mixture prior to polymerization. However, as stated in this patent, see column 6, such films, according to the invention, resist short stresses when washing with soap and water. It is thus acknowledged that the copolymers proposed are not in the accepted sense water-insoluble. This patent is particularly noteworthy with respect to the myriad of requirements for polymer systems having utility as film formers for application to the skin. The copolymer systems proposed therein appear to be capable of satisfying numerous of the requirements, but it is to be noted that such copolymer systems still do not satisfy the significant requirement of providing an essentially water-insoluble film.
From the lengthy discussion in U.S. Pat. No. 3,987,000 with respect to the desired advantageous characteristics of film-forming polymer compositions for application to the skin, it is believed that it will readily be apparent that far more than routine experimentation is required in order to provide a suitable skin protective barrier, or film, based upon known film-forming polymers or copolymers.
In this latter regard, it is recognized that solutions of the n-butyl and isobutyl esters of methacrylic acid, and copolymers thereof, have utility as film formers per se, as will be appreciated from U.S. Pat. No. 2,129,668.
U.S. Pat. No. 2,804,073 is directed to a resinous film-former for application to the skin and wherein there is broadly disclosed the utilization of polymethacrylic ester polymers and compatible combinations thereof. However, insofar as polymethacrylic ester polymers are concerned, the specific Examples, see Example 2, only show the utilization of n-butyl methacrylate polymer.
However, the myriad of interrelated properties essential to the formation and maintenance of a protective barrier film on the skin, particularly for ostomates, presents a highly complex problem that requires far more than routine experimentation in addition to the knowledge that particular polymers, copolymers, etc. have known utility as film formers.